From 88a6f18b950e2e4dce57d31daa151105f4f3dcff Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Sat, 24 Nov 2018 14:46:14 -0700 Subject: [PATCH] aio: split out iocb copy from io_submit_one() In preparation of handing in iocbs in a different fashion as well. Also make it clear that the iocb being passed in isn't modified, by marking it const throughout. Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe --- fs/aio.c | 68 +++++++++++++++++++++++++++++++------------------------- 1 file changed, 38 insertions(+), 30 deletions(-) diff --git a/fs/aio.c b/fs/aio.c index 59044e53b355..278956d53474 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -1422,7 +1422,7 @@ static void aio_complete_rw(struct kiocb *kiocb, long res, long res2) aio_complete(iocb, res, res2); } -static int aio_prep_rw(struct kiocb *req, struct iocb *iocb) +static int aio_prep_rw(struct kiocb *req, const struct iocb *iocb) { int ret; @@ -1463,7 +1463,7 @@ static int aio_prep_rw(struct kiocb *req, struct iocb *iocb) return ret; } -static int aio_setup_rw(int rw, struct iocb *iocb, struct iovec **iovec, +static int aio_setup_rw(int rw, const struct iocb *iocb, struct iovec **iovec, bool vectored, bool compat, struct iov_iter *iter) { void __user *buf = (void __user *)(uintptr_t)iocb->aio_buf; @@ -1502,8 +1502,8 @@ static inline void aio_rw_done(struct kiocb *req, ssize_t ret) } } -static ssize_t aio_read(struct kiocb *req, struct iocb *iocb, bool vectored, - bool compat) +static ssize_t aio_read(struct kiocb *req, const struct iocb *iocb, + bool vectored, bool compat) { struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs; struct iov_iter iter; @@ -1535,8 +1535,8 @@ static ssize_t aio_read(struct kiocb *req, struct iocb *iocb, bool vectored, return ret; } -static ssize_t aio_write(struct kiocb *req, struct iocb *iocb, bool vectored, - bool compat) +static ssize_t aio_write(struct kiocb *req, const struct iocb *iocb, + bool vectored, bool compat) { struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs; struct iov_iter iter; @@ -1591,7 +1591,8 @@ static void aio_fsync_work(struct work_struct *work) aio_complete(container_of(req, struct aio_kiocb, fsync), ret, 0); } -static int aio_fsync(struct fsync_iocb *req, struct iocb *iocb, bool datasync) +static int aio_fsync(struct fsync_iocb *req, const struct iocb *iocb, + bool datasync) { if (unlikely(iocb->aio_buf || iocb->aio_offset || iocb->aio_nbytes || iocb->aio_rw_flags)) @@ -1719,7 +1720,7 @@ aio_poll_queue_proc(struct file *file, struct wait_queue_head *head, add_wait_queue(head, &pt->iocb->poll.wait); } -static ssize_t aio_poll(struct aio_kiocb *aiocb, struct iocb *iocb) +static ssize_t aio_poll(struct aio_kiocb *aiocb, const struct iocb *iocb) { struct kioctx *ctx = aiocb->ki_ctx; struct poll_iocb *req = &aiocb->poll; @@ -1791,27 +1792,23 @@ static ssize_t aio_poll(struct aio_kiocb *aiocb, struct iocb *iocb) return 0; } -static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, - bool compat) +static int __io_submit_one(struct kioctx *ctx, const struct iocb *iocb, + struct iocb __user *user_iocb, bool compat) { struct aio_kiocb *req; - struct iocb iocb; ssize_t ret; - if (unlikely(copy_from_user(&iocb, user_iocb, sizeof(iocb)))) - return -EFAULT; - /* enforce forwards compatibility on users */ - if (unlikely(iocb.aio_reserved2)) { + if (unlikely(iocb->aio_reserved2)) { pr_debug("EINVAL: reserve field set\n"); return -EINVAL; } /* prevent overflows */ if (unlikely( - (iocb.aio_buf != (unsigned long)iocb.aio_buf) || - (iocb.aio_nbytes != (size_t)iocb.aio_nbytes) || - ((ssize_t)iocb.aio_nbytes < 0) + (iocb->aio_buf != (unsigned long)iocb->aio_buf) || + (iocb->aio_nbytes != (size_t)iocb->aio_nbytes) || + ((ssize_t)iocb->aio_nbytes < 0) )) { pr_debug("EINVAL: overflow check\n"); return -EINVAL; @@ -1825,14 +1822,14 @@ static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, if (unlikely(!req)) goto out_put_reqs_available; - if (iocb.aio_flags & IOCB_FLAG_RESFD) { + if (iocb->aio_flags & IOCB_FLAG_RESFD) { /* * If the IOCB_FLAG_RESFD flag of aio_flags is set, get an * instance of the file* now. The file descriptor must be * an eventfd() fd, and will be signaled for each completed * event using the eventfd_signal() function. */ - req->ki_eventfd = eventfd_ctx_fdget((int) iocb.aio_resfd); + req->ki_eventfd = eventfd_ctx_fdget((int) iocb->aio_resfd); if (IS_ERR(req->ki_eventfd)) { ret = PTR_ERR(req->ki_eventfd); req->ki_eventfd = NULL; @@ -1847,32 +1844,32 @@ static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, } req->ki_user_iocb = user_iocb; - req->ki_user_data = iocb.aio_data; + req->ki_user_data = iocb->aio_data; - switch (iocb.aio_lio_opcode) { + switch (iocb->aio_lio_opcode) { case IOCB_CMD_PREAD: - ret = aio_read(&req->rw, &iocb, false, compat); + ret = aio_read(&req->rw, iocb, false, compat); break; case IOCB_CMD_PWRITE: - ret = aio_write(&req->rw, &iocb, false, compat); + ret = aio_write(&req->rw, iocb, false, compat); break; case IOCB_CMD_PREADV: - ret = aio_read(&req->rw, &iocb, true, compat); + ret = aio_read(&req->rw, iocb, true, compat); break; case IOCB_CMD_PWRITEV: - ret = aio_write(&req->rw, &iocb, true, compat); + ret = aio_write(&req->rw, iocb, true, compat); break; case IOCB_CMD_FSYNC: - ret = aio_fsync(&req->fsync, &iocb, false); + ret = aio_fsync(&req->fsync, iocb, false); break; case IOCB_CMD_FDSYNC: - ret = aio_fsync(&req->fsync, &iocb, true); + ret = aio_fsync(&req->fsync, iocb, true); break; case IOCB_CMD_POLL: - ret = aio_poll(req, &iocb); + ret = aio_poll(req, iocb); break; default: - pr_debug("invalid aio operation %d\n", iocb.aio_lio_opcode); + pr_debug("invalid aio operation %d\n", iocb->aio_lio_opcode); ret = -EINVAL; break; } @@ -1894,6 +1891,17 @@ static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, return ret; } +static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, + bool compat) +{ + struct iocb iocb; + + if (unlikely(copy_from_user(&iocb, user_iocb, sizeof(iocb)))) + return -EFAULT; + + return __io_submit_one(ctx, &iocb, user_iocb, compat); +} + /* sys_io_submit: * Queue the nr iocbs pointed to by iocbpp for processing. Returns * the number of iocbs queued. May return -EINVAL if the aio_context